config HAVE_ARCH_KASAN
  	bool
  
  if HAVE_ARCH_KASAN
  
  config KASAN
  	bool "KASan: runtime memory debugger"

  	depends on SLUB || (SLAB && !DEBUG_SLAB)

  	select CONSTRUCTORS

  	select STACKDEPOT

  	help
  	  Enables kernel address sanitizer - runtime memory debugger,
  	  designed to find out-of-bounds accesses and use-after-free bugs.

  	  This is strictly a debugging feature and it requires a gcc version
  	  of 4.9.2 or later. Detection of out of bounds accesses to stack or
  	  global variables requires gcc 5.0 or later.
  	  This feature consumes about 1/8 of available memory and brings about
  	  ~x3 performance slowdown.

  	  For better error detection enable CONFIG_STACKTRACE.

  	  Currently CONFIG_KASAN doesn't work with CONFIG_DEBUG_SLAB
  	  (the resulting kernel does not boot).

  config KASAN_EXTRA
  	bool "KAsan: extra checks"
  	depends on KASAN && DEBUG_KERNEL && !COMPILE_TEST
  	help
  	  This enables further checks in the kernel address sanitizer, for now
  	  it only includes the address-use-after-scope check that can lead
  	  to excessive kernel stack usage, frame size warnings and longer
  	  compile time.
  	  https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81715 has more

  choice
  	prompt "Instrumentation type"
  	depends on KASAN
  	default KASAN_OUTLINE
  
  config KASAN_OUTLINE
  	bool "Outline instrumentation"
  	help
  	  Before every memory access compiler insert function call
  	  __asan_load*/__asan_store*. These functions performs check
  	  of shadow memory. This is slower than inline instrumentation,
  	  however it doesn't bloat size of kernel's .text section so
  	  much as inline does.
  
  config KASAN_INLINE
  	bool "Inline instrumentation"
  	help
  	  Compiler directly inserts code checking shadow memory before
  	  memory accesses. This is faster than outline (in some workloads
  	  it gives about x2 boost over outline instrumentation), but
  	  make kernel's .text size much bigger.

  	  This requires a gcc version of 5.0 or later.

  
  endchoice

  config TEST_KASAN
  	tristate "Module for testing kasan for bug detection"
  	depends on m && KASAN
  	help
  	  This is a test module doing various nasty things like
  	  out of bounds accesses, use after free. It is useful for testing
  	  kernel debugging features like kernel address sanitizer.

  endif